Multi-mode stereoscopic imaging system

Abstract

A multi-mode stereoscopic imaging system is described. It is the first stereo system which is convertible back and forth from the auto stereo viewing mode without glasses to the binocular stereo viewing mode with glasses. It is based on micro-polarizer arrays and spatial multiplexing of images. The system consists of a stereo image component and an auto parallax barrier component. Both components use the properties of μPols. Switching from one mode to the other is accomplished manually, and electronically with the aid of a liquid crystal light valve. The system combines the benefits of auto-stereo imaging and the binocular stereo imaging of prior art techniques without their limitations.

What is claimed is:  
     
       1. A multi-mode image display system having a 3-D viewing mode for visually displaying a polarized spatially multiplexed image of a 3-D object, and a 2-D viewing mode for visually displaying selected image components of said polarized spatially multiplexed image, said multi-mode image display system comprising: 
       an electro-optical display device having a display surface and means for visually displaying on said display surface, a composite pixel pattern representative of a spatially multiplexed image composed of first and second spatially modulated perspective images of said object, said first spatially modulated perspective image consisting of a first pixel pattern representative of a first perspective image of said object spatially modulated according to a first spatial modulation pattern, said second spatially modulated perspective image consisting of a second pixel pattern representative of a second perspective image of said object spatially modulated according to a second spatial modulation pattern, said second spatial modulation pattern being the logical compliment pattern of said first spatial modulation pattern;  
       a micropolarization panel of electrically-passive construction, including first and second optically transparent patterns permanently formed therein,  
       said first optically transparent pattern spatially corresponding to and being spatially aligned with said first pixel pattern displayed on said display surface so as to impart a first polarization state P1 to light emanating from said first pixel pattern and passing through said first optically transparent pattern, and  
       said second optically transparent pattern spatially corresponding to and being spatially aligned with said second pixel pattern displayed on said display surface so as to impart a second polarization state P2 to light emanating from said second pixel pattern and passing through said second optically transparent pattern, said second polarization state P2 being different than said first polarization state P1, and  
       said polarized light passing through said first and second optically transparent patterns forming a polarized spatially multiplexed image for use in stereoscopic viewing said 3-D object; and  
       light transmission means for transmitting polarized light with both said first and second polarization states P1 and P2 from said micropolarization panel towards the eyes of the viewer during said 3-D viewing mode, and transmitting polarized light with either said first polarization state P1 or said second polarization state P2 from said micropolarization panel towards the eyes of the viewer during said 2-D viewing mode.  
     
     
       2. The multi-mode image display system of claim  1 , wherein said first optically transparent pattern comprises a first polarization pattern which imparts said first polarization state P1 to light emanating from said first pixel pattern and passing through said first polarization pattern, and wherein said second optically pattern comprises a second polarization pattern which imparts said polarization state P2 to light emanating from said second pixel pattern and passing through said second polarization pattern. 
     
     
       3. The multi-mode image display system of claim  2 , wherein said light transmission means comprises a polarization sheet. 
     
     
       4. The multi-mode image display system of claim  3 , wherein said polarization sheet has either polarization state P1 or P2. 
     
     
       5. The multi-mode image display system of claim  4 , wherein said light transmission means further comprises means for moving said polarization sheet in front of said micropolarization panel during said 2-D viewing mode, and away from said micropolarization panel during said 3-D viewing mode. 
     
     
       6. The multi-mode image display system of claim  1 , wherein said electro-optical display device is selected from the group consisting of a CRT display device and a liquid crystal display device. 
     
     
       7. The multi-mode image display system of claim  1 , in combination with 
       an optical viewing device of electrically-passive construction, having a head supportable frame within which first and second optically transparent elements are mounted,  
       said first optically transparent element being positionable adjacent to the left eye of a viewer, and  
       said second optically transparent element being positionable to the right eye of the viewer,  
       wherein said first optically transparent element is characterized by said first polarization state P1 so as to permit, during said 3-D viewing mode, the left eye of the viewer to view said first pixel pattern displayed on said display surface, while substantially preventing the left eye of the viewer from viewing said second pixel pattern displayed on said display surface,  
       wherein said second optically transparent element is characterized by said second polarization state P2 so as to permit, during said 3-D viewing mode, the right of the viewer to view said second pixel pattern displayed on said display surface while substantially preventing the right eye of the viewer from viewing said first pixel pattern displayed on said display surface, and  
       whereby the viewer stereoscopically views said 3-D object.